Transient pseudo-hypoaldosteronism following resection of the ileum: normal level of lymphocytic aldosterone receptors outside the acute phase.

Pseudo-hypoaldosteronism (PHA) is due to mineralocorticoid resistance and manifests as hyponatremia and hyperkalemia with increased plasma aldosterone levels. It may be familial or secondary to abnormal renal sodium handling. We report the case of a 54-year-old woman with multifocal cancer of the colon, who developed PHA after subtotal colectomy, ileal resection and jejunostomy. She was treated with 6 g of salt daily to prevent dehydration, which she stopped herself because of reduced fecal losses. One month later she was admitted with signs of acute adrenal failure, i.e. fatigue, severe nausea, blood pressure of 80/60 mmHg, extracellular dehydration, hyponatremia (118 mmol/l); hyperkalemia (7.6 mmol/l), increased blood urea nitrogen (BUN) (200 mg/dl) and creatininemia (2.5 mg/dl), and decreased plasma bicarbonates level (HCO3-: 16 mmol/l; N: 27-30). However, the plasma cortisol was high (66 microg/100 ml at 10:00 h; N: 8-15) and the ACTH was normal (13 pg/ml, N: 10-60); there was a marked increase in plasma renin activity (>37 ng/ml/h; N supine <3), active renin (869 pg/ml; N supine: 1.120), aldosterone (>2000 pg/ml; N supine <150) and plasma AVP (20 pmol/l; N: 0.5-2.5). The plasma ANH level was 38 pmol/l (N supine: 5-25). A urinary steroidogram resulted in highly elevated tetrahydrocortisol (THF: 13.3 mg/24h; N: 1.4+/-0.8) with no increase in tetrahydrocortisone (THE: 3.16 mg/24h; N: 2.7+/-2.0) excretion, and with low THE/THF (0.24; N: 1.87+/-0.36) and alpha THF/THF (0.35; N: 0.92+/-0.42) ratios. The number of mineralocorticoid receptors in mononuclear leukocytes was in the lower normal range for age, while the number of glucocorticoid receptors was reduced. Small-bowel resection in ileostomized patients causes excessive fecal sodium losses and results in chronic sodium depletion with contraction of the plasma volume and severe secondary hyperaldosteronism. Nevertheless, this hyperaldosteronism may be associated with hyponatremia and hyperkalemia suggesting PHA related to the major importance of the colon for the absorption of sodium. In conclusion, this case report emphasizes 1) the possibility of a syndrome of acquired PHA with severe hyperkalemia after resection of the ileum and colon responding to oral salt supplementation; 2) the major increase in AVP and the small increase in ANH; 3) the strong increase in urinary THF with low THE/THF and alpha THF/THF ratios; 4) the normal number of lymphocytic mineralocorticoid receptors outside the acute episode.

Hypocalcemia following thyroid surgery: incidence and prediction of outcome.

Postoperative hypocalcemia is a common and most often transient event after extensive thyroid surgery. It may reveal iatrogenic injury to the parathyroid glands and permanent hypoparathyroidism. We prospectively evaluated the incidence of hypocalcemia and permanent hypoparathyroidism following total or subtotal thyroidectomy in 1071 consecutive patients operated during 1990-1991. We then determined in a cross-sectional study which early clinical and biochemical characteristics of patients experiencing postoperative hypocalcemia correlated with the long-term outcome. Postoperative calcemia under 2 mmol/l was observed in 58 patients (5. 4%). In 40 patients hypocalcemia was considered severe (confirmed for more than 2 days, symptomatic or both). At 1 year after surgery five patients (0.5%) had persistent hypocalcemia. We found that patients carried a high risk for permanent hypoparathyroidism if fewer than three parathyroid glands were preserved in situ during surgery or the early serum parathyroid hormone level was /= 4 mg/dl under oral calcium therapy. When one or more of these criteria are present, long-term follow-up should be enforced to check for chronic hypocalcemia and to avoid its severe complications by appropriate supplement therapy.

[comparison of the effects on phosphocalcic metabolism and bone of 3 protocols of vitamin D administration in the elderly]. / Comparaisons des effets sur le métabolisme phosphocalcique et sur l'os de trois protocoles d'administration pendant un an de la vitamine D chez la personne âgée.

According to recent studies, vitamin D deficiency may contribute to the osteoporosis observed in elderly subjects, with reduced intestinal calcium absorption and secondary hyperparathyroidism. Vitamin D deficiency is often present in elderly people, due to inadequate diet and confinement at home. The administration of either oral vitamin D in doses of 4,000 IU per day, or six-monthly intramuscular injections of ergocalciferol 600,000 IU, combined with a daily intake of at least 1 g of calcium brings back to normal both 25 OH D concentrations and parathyroid hormone levels. When pursued for one year, these treatments also maintain the formation of cortical bone, as shown by the metacarpal index. As for the concentration of 25 OH D, it seems that 60 to 75 nmol/l are necessary to restore calcium homeostasis. The dietary habits of elderly people are such that a supplement of medicinal calcium is required. Finally, we regard the parenteral form of ergocalciferol as being preferable to the oral form at that age for better compliance with treatment.

[Phosphocalcium metabolism in the elderly. Study of 101 subjects living in an institution]. / Etude du métabolisme phosphocalcique de la personne âgée chez 101 sujets vivant en institution.

Calcium and phosphorus metabolism was studied in 101 institutionalized subjects over 70 years of age (mean: 82.5 years). The study was performed in serum and urine; it included parathyroid hormone and calcidiol (250HD3) assays and radiological examination of bones with determination of Meunier's index and metacarpal cortical index. Calcidiol concentrations did not vary with age but were higher in people who left the institution and in men. In contrast, there was a significant age-group related increase of parathyroid hormone concentrations. This increase was accompanied by an increase of parathyroid hormone activity, as shown by a parallel fall in phosphorus reabsorption rate. These findings are in agreement with current pathogenetic theories on senile osteoporosis. Invalid subjects had higher urinary calcium and serum parathyroid hormone levels and a lower cortical index. Paradoxically, there was less vertebral collapse as evaluated by Meunier's index, which may suggest that very old patients develop progressive cortical bone hyperresorption entirely independent of sequelae from their former trabecular osteoporosis.